Biofilters which are used to purify and control the odor of wastewaters and waste gases, are known from the generally known prior art. Such biofilters include a filter layer and an air distribution chamber into which a steam-saturated crude gas is introduced. Different composts such as; bark compost, green compost, ground root wood, chopped wood bark, peat, coconut fibers, etc. as well as mixtures of these materials can be used as traversed filter material. A combination of this type of biofilter with an upstream biowasher is also known in the filtering processes.
Highly toxic organic compounds, dioxins and furans which are contained in waste gases, incineration gases, industrial exhaust, etc., pose greater problems. During disposal or purification of such waste gases, specially developed, expensive high-tech equipment is required.